Modular prefilled hydraulic control apparatus

ABSTRACT

A hydraulic control apparatus, more particularly for operating a motor vehicle clutch release mechanism, comprising a master cylinder, a slave cylinder and a conduit connecting the master cylinder to the slave cylinder. The apparatus is in the form of separate modular units which are separately filled with hydraulic fluid, and the filled modular units are shipped unconnected to a user. Each modular unit is provided with a leakproof quick-connect connector member, through which filling of the modular unit may be effected, and which mates with a complementary leakproof quick-connect connector member of another modular unit, such that after installation on a utiization device, a motor vehicle for example, complementary connector members are reconnected, thus opening ports in each connector member placing each member in fluid communication with the other. Preferably, the two connector members are provided with a one-way locking arrangement preventing separation of the connector members after coupling. Alternatively, the two connector members may be disconnected by a special tool to enable disconnecting the members without loss of hydraulic fluid, for the purpose of repair or replacement of components.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation-in-part of application Ser.No. 555,667, filed Nov. 28, 1983, and is related to application Ser. No.680,329, filed Jan. 17, 1985, which is also a continuation-in-part ofapplication Ser. No. 555,667.

BACKGROUND OF THE INVENTION

The present invention relates to hydraulic apparatus in general, andmore particularly to a hydraulic control apparatus comprising ahydraulic master cylinder and a hydraulic slave cylinder for operating amechanism remotely located from the master cylinder, the hydrauliccontrol apparatus being prefilled with hydraulic fluid and pretestedprior to shipment to a motor vehicle manufacturer, for example forinstallation in a motor vehicle.

It is now known to prefill with hydraulic fluid a motor vehicle clutchcontrol apparatus, comprising a master cylinder, a reservoir ofhydraulic fluid, and a slave cylinder for operating the throwout bearingof a mechanical diaphragm spring clutch, as disclosed in British Pat.No. 1,539,879 and in corresponding U.S. Pat. No. 4,407,125, and inco-pending applications Ser. Nos. 371,958 and 376,248, filedrespectively Apr. 26, 1982 and May 10, 1982, and assigned to the sameassignee as the present application. In addition U.S. Pat. Nos.4,503,678 and 4,506,507, co-pending applications Ser. Nos. 477,159,477,160, 477,161 and 477,162, all filed Mar. 21, 1983 and assigned tothe same assignee as the present application, also disclose diverseforms of prefilled hydraulic control apparatus for motor vehicleclutches, and co-pending applications Ser. Nos. 555,666 and 555,668filed Nov. 28, 1983, and assigned to the same assignee as the presentapplication, disclose prefilled hydraulic control apparatus fortransmission shifting mechanisms and throttle mechanisms, respectively.

Prefilling with hydraulic fluid and pretesting hydraulic apparatus foroperating motor vehicle mechanisms such as mechanical clutches presentthe many advantages, for the motor vehicle manufacturer, of receiving afully assembled mechanism comprising all the components filled withhydraulic fluid and pretested for proper operation, ready to install ona motor vehicle on the assembly line, without requiring that thecomponents be installed separately, connected by way of a flexibleconduit, and filled after installation with hydraulic fluid while beingpurged of any atmospheric air contained in the apparatus.

In apparatus wherein the slave cylinder, actuating the clutch releasemechanism, takes the form of a conventional cylindrical cylinder-pistonassembly with the piston rod projecting from the cylinder housingattached at its end to the clutch release lever, the slave cylinderbeing attached at some portion of the clutch bell housing, permanentconnection of the master cylinder to the slave cylinder by means of aflexible conduit, and prefill of the apparatus with hydraulic fluid donot present much inconvenience, whether the slave cylinder or the mastercylinder is installed first on the vehicle, and the other cylinderinstalled at some other subsequent station on the assembly line. Thelast installed component may be simply left dangling on the end of theflexible conduit, or may be attached by means of straps, wires orstrings to some portion of the motor vehicle frame or body, untildefinitely mounted in its operative position. However, with the presenttrend towards utilizing annular slave cylinders, disposed concentric tothe driveshaft and bolted either to the face of the transmission orgearbox casing or, in the alternative, mounted on or made integral withthe clutch bell housing, such that the annular piston within theconcentric annular slave cylinder may operate the clutch throwoutbearing, it is difficult to provide a fully assembled, fully tested,prefilled apparatus, without some accompanying inconveniences. Suchinconveniences relate to the requirement that the annular slave cylinderbe installed first in the clutch bell housing, or on the transmissioncasing face, and the master cylinder on the end of the flexible line orconduit interconnecting the master and slave cylinders be provisionallyattached, in some manner by strings, wires or straps to the motorvehicle frame, and subsequently installed in its proper position throughthe passenger compartment floorboard or bulkhead.

The invention disclosed in application Ser. No. 555,667 remedies theinconveniences enumerated hereinbefore with respect to preassembledprefilled hydraulic control apparatus for motor vehicle mechanicalclutches, more particularly in structures wherein the throwout bearingis operated by a concentric annular slave cylinder, while presenting allthe advantages of prefilled and pretested clutch control apparatus. Suchresults are achieved by a pretested prefilled hydraulic clutch controlmechanism provided with an irreversible one-way quick-connect fitting orconnector either at some point of the flexible conduit connecting themaster cylinder to the slave cylinder, or at the end of the conduitconnected to the master cylinder, or at the end of the conduit connectedto the slave cylinder. The one-way quick-connect fitting or connector isarranged such that after the hydraulic control mechanism has beenassembled, prefilled with hydraulic fluid and pretested, the connectionbetween the master cylinder and the slave cylinder may be broken,without loss of fluid, or negligible loss of fluid, and the apparatusmay be shipped to the motor vehicle manufacturer, completely filled withhydraulic fluid but in two separate portions such that the concentricslave cylinder may be made a part of the clutch bell housing, or of thetransmission casing, and thus installed in the motor vehicle at whateverstation on the assembly line that the clutch or transmission isinstalled, and such that the master cylinder may be installed in themotor vehicle also at whatever appropriate station, and the twoconnected together without any loss, or negligible loss, of fluid andwithout introduction of air into the apparatus.

SUMMARY OF THE INVENTION

The present invention also has for principal object to provide aprefilled hydraulic clutch control mechanism provided with a one-wayquick connect fitting or connector between the master cylinder and theslave cylinder. The one-way quick connect fitting or connector may bedisposed at either end of the flexible line or conduit connecting themaster cylinder to the slave cylinder, or may be disposed at someintermediary point between the ends of the flexible conduit. The one-wayquick connect fitting or connector is made of two half-connectors, afemale member and a male member which, once coupled, cannot beuncoupled. In the alternative, where it is desired to enable thequick-connect fitting or connector halves to be uncoupled for thepurpose of part replacement or repair, they can be uncoupled only bymeans of a special tool.

The present invention, as the one disclosed in copending applicationSer. No. 555,667, permits to assemble a hydraulic control apparatus,prefill it with hydraulic fluid and pretest it. After this has beenaccomplished, the connection between the master cylinder and the slavecylinder may be broken, without loss of fluid, or negligible loss offluid, and the apparatus may be shipped to a motor vehicle manufacturer,completely filled with hydraulic fluid but in two or three separateportions, such that the slave cylinder may be made a part of the clutchbell housing, or the transmission casing, and thus installed in themotor vehicle at whatever convenient station on the assembly line thatthe clutch or transmission is installed, and such that the mastercylinder may be installed in the motor vehicle at whatever appropriatestation of the assembly line, and the two connected together without anyloss of fluid and without the introduction of air into the apparatus. Inaddition, the present invention permits to prefill the hydraulic controlapparatus in its separate portions, and to connect the portions on theassembly line without loss of fluid and without introduction of air intothe apparatus, thus doing away with the requirement of filling theapparatus with hydraulic fluid and appropriately bleeding the apparatusafter installation on a motor vehicle on the assembly line. Furthermore,the present invention permits to effectuate any repair on the motorvehicle requiring disconnecting the master cylinder from the slavecylinder, such as for example effecting repairs on the engine, on theclutch or on the transmission, which may require removal of a componentfrom the motor vehicle and disconnecting the slave cylinder from themaster cylinder especially in installations wherein the slave cylinderis an annular cylinder mounted around the motor vehicle driveshaft. As afurther advantage, the present invention permits to replace one of thecomponents of the hydraulic control apparatus without the requirement ofreplacing the other components and without the requirement of refillingand bleeding the whole system after replacement of a component. Thepresent invention has many applications to other automotive mechanisms,such as hydraulic brake system, hydraulic gear shifters and hydraulicthrottle controls, for example.

Other objects and advantages of the present invention will becomeapparent to those skilled in the art when the following description ofthe best modes contemplated for practicing the invention is read inconjunction with the accompanying drawing wherein like referencenumerals refer to like or equivalent parts, and in which:

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a schematic representation of a clutch hydraulic controlapparatus according to the present invention;

FIGS. 2 through 4 are views generally similar to FIG. 1 but showingmodifications thereof;

FIG. 5 is a partial section along line 5--5 of FIG. 3;

FIG. 6 is a view similar to FIG. 5, but showing the two separate halvesof a leakproof quick-connect fitting or connector forming part of thepresent invention, prior to coupling;

FIG. 7 is a transverse section along line 7--7 of FIG. 6;

FIG. 8 is a partial section along line 8--8 of FIG. 4;

FIG. 9 is a partly schematic view illustrating the manner in which aportion of the hydraulic control apparatus of the invention is prefilledwith hydraulic fluid;

FIG. 10 is a view similar to FIG. 9, but showing a modification thereof;

FIG. 11 is a partial section through a leakproof quick-connect fittingor connector according to the present invention showing a modificationpermitting to disconnect the male and female members of the fitting bymeans of an example of a special disconnect tool;

FIG. 12 is a view from line 12--12 of FIG. 11;

FIG. 13 is a partial section along line 13--13 of FIG. 12; and

FIGS. 14-15 are examples of further applications of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the drawing, and more particularly to FIG. 1, a motorvehicle transmission is schematically illustrated as comprising afriction clutch assembly 11 and a gearbox 12 enclosed in a casing orhousing 15. A driveshaft 13 drives the gearbox 12 from the clutchassembly 11. A bell housing 14, surrounding the clutch assembly 11, isbolted on the rear face of the motor vehicle engine E. The rear face 16of the bell housing 14 is bolted to the face 17 of the gearbox casing15. An annular hydraulic slave cylinder 18 is disposed around thedriveshaft 13 within the bell housing 14. In the example of structureillustrated, the slave cylinder 18 has a one-piece housing 20 castintegral with the clutch bell housing 14. The face 17 of the gearboxcasing 20 is on a flange 22, and an end plate, not shown, closing theend of the gearbox casing 15 is also bolted to the face 17 of thegearbox casing 15, the transmission input shaft 13, as shown in dashedlines, projecting through the end plate 24.

The slave cylinder 18 is connected via a line or conduit 26 to a mastercylinder 28. The master cylinder 28 is provided with a built-inhydraulic fluid reservoir 29, in the example of structure illustrated,and has an input rod 30 pivotally connectable at an end to a clutchcontrol pedal, not shown, installed within the driver compartment of amotor vehicle, not shown. The rod 30, as is well known, is connected toa piston, not shown, disposed in the master cylinder 28 for displacingthe hydraulic fluid through the line 26 to the slave cylinder 18 whenthe clutch pedal is depressed. The line or conduit 26 is a flexibleconduit or hose having a connector 32 for connection to the inlet of theslave connector 18, and has another connector 34 on the other end forconnection to the outlet of the master cylinder 28.

Although the slave cylinder 18 is, in the illustrated example ofstructure, of the type having a housing 20 which is formed integral withthe clutch bell housing 14, it will be appreciated that the slavecylinder may in the alternative, be formed integral with thetransmission or gearbox casing end plate, as disclosed in details inapplication Ser. No. 537,869, filed Sept. 30, 1983 and assigned to thesame assignee as the present application. In such structures, the slavecylinder 18 is already integral or preassembled to the clutch bellhousing 14, as illustrated, when the bell housing is bolted to thegearbox casing 15 during assembly of a motor vehicle or, in itsalternate configuration, not shown here, the slave cylinder is alreadypreassembled to the transmission or gearbox casing 15 by being made partof the casing end plate. It will be appreciated by those skilled in theart that the invention may be used in combination with any type ofconcentric slave cylinder as disclosed in detail in the aforesaidco-pending application, Ser. No. 537,869, or to any hydraulic controlapparatus for a motor vehicle mechanical clutch, whether utilizing aconcentric slave cylinder or a more conventional cylindrical slavecylinder.

The slave cylinder 18, as disclosed in detail in the aforesaid pendingapplication, is adapted to displace a throwout bearing 36 engaged withthe end of the clutch release fingers 38, for releasing the clutch 11when hydraulic fluid is introduced into the slave cylinder 18 from themaster cylinder 28 through the conduit 26. After manufacturing andassembly of the hydraulic apparatus, and prior to filling the apparatuswith hydraulic fluid, a restraining strap 40, of the type disclosed inmore details for example in copending application Ser. No. 537,869,filed Aug. 30, 1983 and assigned to the same assignee as the presentapplication is installed for holding the throw-out bearing 36 in aretracted position, during shipment of the hydraulic apparatus andinstallation of the integral subassembly of the slave cylinder 18 andbell housing 14 on a motor vehicle, in the example of structureillustrated. During filling with hydraulic fluid of the hydraulicapparatus, and during shipment and installation of the master cylinder28 on a motor vehicle, the input rod 30 of the master cylinder is heldin an extended position by means such as a clip 42, for example, asdisclosed in more detail in copending application Ser. No. 509,998, alsoassigned to the same assignee as the present application.

In the example of structure illustrated at FIG. 1, the fitting orconnector 32, connecting an end of the conduit 26 to the master cylinder28, is of the leakproof quick-connect type, while the fitting orconnector 34 connecting the other end of the conduit 26 to the slavecylinder 18 is of the conventional type. In this manner, after thehydraulic apparatus has been filled with hydraulic fluid, the line orconduit 26 may be broken at the connector 32 without loss of hydraulicfluid or, in the alternative, and as hereinafter explained, the mastercylinder 28 may be prefilled with hydraulic fluid as a separate firstmodular unit, while the slave cylinder 18 and the conduit 26 may befilled with hydraulic fluid as a separate second modular unit, the twoseparate modular units being reconnected after installation of thehydraulic apparatus on a motor vehicle.

In the example of structure of FIG. 2, the leakproof quick-connectconnector 32 is used for connecting one end of the line 26 to the slavecylinder 18, while the other end of the conduit 26 connected to themaster cylinder 28 is provided with a conventional connector 34. Thehydraulic apparatus may thus be broken at the leakproof quick-connectconnector 32, after filling and testing of the apparatus, or, in thealternative, the separate modular units consisting of the mastercylinder 28 with the hose or conduit 26 attached thereto, and of theslave cylinder 18, contained within the bell housing 14, may beseparately prefilled and readily connected after installation of theunits on a motor vehicle.

FIG. 3 illustrates a clutch hydraulic control apparatus according to thepresent invention wherein the conduit 26 is connected to the mastercylinder 28 by way of a conventional connector 34 attached to an end ofthe conduit and the other end of the conduit 26 is connected to theslave cylinder 18 also by way of a conventional connector 34. At somepoint between the ends of the conduit 26, a leakproof quick-connectconnector 32 is disposed such as to permit installing the mastercylinder 28 on a motor vehicle with a portion of the conduit 26 attachedthereto, and to permit installing the slave cylinder 18 on the motorvehicle already pre-installed in or made integral with the bell housing14, in the structure illustrated, or pre-installed on, or integral with,the transmission end cover. The hydraulic apparatus may be prefilledwith hydraulic fluid and pretested in the manufacturer's plant as acomplete assembly, or it may be prefilled and pretested in separatemodular sub-assemblies, one consisting of the slave cylinder 18 with aportion of the conduit 26 attached thereto, and the other consisting ofthe master cylinder 28 with the other portion of the conduit 26 attachedthereto, and the connection between the ends of the portions of theconduit 26 each provided with one-half of the leakproof quick-connectconnector 32 is effected during assembly of the motor vehicle.

FIG. 4 illustrates an extreme arrangement for a hydraulic controlapparatus according to the invention having practical applicationsespecially in installations wherein the master cylinder 28 and the slavecylinder 18 are located at considerable distance from each other, suchas for example in a rear-engine motor coach or the like, and the routingof the flexible conduit 26 through the frame or the body of the motorvehicle is more conveniently effected with the ends of the conduit 26unattached to the master cylinder 28 and to the slave cylinder 18,respectively. The conduit 26 is provided with a leakproof quick-connectconnector 32 at each end, and such an arrangement still permits toeffectuate a bench filling of the apparatus with hydraulic fluid andtesting of the apparatus prior to shipment to the motor vehiclemanufacturer. The apparatus is subsequently broken in three separatecomponents or modular units, already filled with hydraulic fluid, onebeing the master cylinder 28, the other the slave cylinder 18 and thethird one the conduit 26. During assembly of the motor vehicle, thethree separate components are interconnected without loss of fluid andwithout introduction of air in the system. Furthermore, if so desirable,the master cylinder 28, the slave cylinder 18 and the conduit 26 may beprefilled and pretested individually.

As illustrated in detail at FIGS. 5 and 6, the leakproof quick-connectconnector 32 of FIG. 3 consists of two complementary half-connectors ormembers 44 and 46, each formed of a tubular body 47 and 49,respectively. As logic indicates, the half-connector 44 is of the femaletype and its tubular body 47 has a bore 48 capable of slidably acceptingthe cylindrical peripheral surface 50 of the tubular body 49 of thehalf-connector 46, which is evidently of the male type. FIG. 5illustrates the two female and male members 44 and 46 coupled, as alsoshown at FIG. 3, while FIG. 6 illustrates the female member 44 and themale member 46 uncoupled prior to introducing the tubular body 49 of themale member 46 into the bore 48 of the female member 44, afterinstallation of the master cylinder 28 and of the slave cylinder18-clutch bell housing 14 sub-assembly in their respective locations ona motor vehicle.

The tubular body 47 of the female member 44 has an end cap 52 providedwith an integral outwardly projecting fitting 54, a passageway 56permitting fluid communication with the interior of the conduit 26having its end fitted over the fitting 54, and being adequately clampedthereon or, as illustrated, being elastically held over by means of apair of tapered annular ridges 58 projecting from the peripheral surfaceof the fitting 54. The end cap 52 fits in an enlarged diameter endportion 60 of the bore 48 and is held in assembly by means of a springsteel snap-ring 62 elastically expanded in a groove 64, interiorlyformed proximate the end of the tubular housing 47. The interior endface 66 of the end cap 52 is recessed as a result of being provided withan integral projecting annular ridge or rim 68 forming an end annularabutment surface 70. The annular rim 68 has an outer peripheral surfacespaced from the internal surface of the enlarged diameter portion 60 ofthe bore 48, such as to form an L-shaped groove 72 in which is disposedan elastomeric O-ring 73. A circular plate 74 of a diameter permittingfitting thereof within the enlarged diameter portion 60 of the bore 48is engaged on one side with the annular abutment surface 70 of the endcap 52, and on its other side with an annular shoulder 76 formed at thejunction between the bore 48 of the tubular body 47 and the enlargeddiameter bore portion 60 in which is fitted the end cap 52, such as tofixedly hold the circular plate 74 in position as shown. The circularplate 74 supports a rod 78 at its enlarged foot portion 80 having amounting stem 82 passed through a central aperture 84 in the circularplate 74, the projecting end of the stem 82 being formed as a rivet head86 for holding the rod 78 fixedly about the longitudinal axis of thebore 48. Apertures, such as shown at 88, are provided through thecircular plate 74 such as to permit hydraulic fluid to circulate to andfro between the passageway 56 and a chamber 90 defined in the bore 48 ofthe female member 44 below a generally cup-shaped spool valve 92slidably disposed in the bore 48. The rod 78 has an enlarged head 94provided with a groove 96 in which is disposed an elastomeric O-ring 94.The top of the enlarged head 98 forms a circular abutment surface 100and the bottom of the enlarged head 94 forms a tapered abutment surface102. The valve spool 92 has an internally directed boss 104 providedwith a port defined by a bore 106 capable of accepting the rod enlargedhead 94 when the spool valve 92 is displaced by a compressed coil spring108, disposed between the circular plate 74 and the cup-shaped spoolvalve 92, urging the spool valve 92 to the position shown at FIG. 6,causing engagement of the tapered abutment face 102 with a correspondingtapered abutment end surface 110 at the end of the bore 106 within thevalve spool boss 104.

It is immediately apparent that in the position of the spool valve 92illustrated at FIG. 6, the enlarged head 94 of the rod 78 being engagedwithin the port defined by the bore 106 in the spool valve boss 104, theelastomeric O-ring 98 in the groove 96 prevents leakage of fluid fromthe chamber 90 to the open end of the female member tubular body 47. Anelastomeric O-ring 112, disposed in an annular groove 114 in the surfaceof the bore 48 prevents leakage of fluid past the peripheral surface ofthe spool valve 92, the elastomeric O-ring 74 evidentally preventingleakage of fluid past the end cap 52. The bore 48 in the female membertubular body 47 is further provided with an internal groove 116 in whichis disposed an elastomeric O-ring 118, the groove 116 and theelastomeric O-ring 118 being located proximate the open end of thetubular body 47 beyond the annular end face 120 of the spool valve 92. Afurther annular groove 122 is formed proximate the end of the tubularbody 47. The groove 122 has a tapered sidewall 124 and a radial sidewall125, and the bore 48 gradually increases in diameter at the end of thetubular body 47, such as to form a funnel-shaped or tapered wall 126.

The tubular body 49 of the male member 46 has an internal bore 128provided with an enlarged diameter end bore portion 130 in which isfitted an end cap 52 identical to the end cap 52 closing the end of thetubular body 47 of the female member 44. The fitting 54 of the malemember end cap 52 is attached to the end of the corresponding length ofconduit 26, and the passageway 56 through the fitting 54 and the end cap52 allows transfer of hydraulic fluid to and fro between the conduit 26and an internal chamber 132 defined in the bore 128 of the male membertubular body 50. Utilizing identical end caps 52 for the male member 46and the female member 44 results in a considerable reduction of partinventory.

A spider member 134 has legs 135, three in number, FIG. 7, in theexample of structure illustrated, radially extending for slidingengagement with the surface of the internal bore 128 such as to providelateral support for the spider member 134. The spider member 134 has afrontal abutment 136 engageable with an abutment annular surface 138formed between the principal bore 128 within the tubular body 50 and aport in the form of a reduced diameter end bore portion 140. The spidermember 134 supports, or is made integral with, a head or spool 142 of anouter diameter fitting the reduced diameter end bore 140, and providedwith a groove 144 containing an elastomeric O-ring 146. The spool 142has a flat abutment end face 148. A coil spring 150 disposed incompression between the annular recessed face 66 of the end cap 52 andthe rear face 152 of the spider member 134 normally urges the spidermember 134 and the spool 142 carried on the end thereof to the positionshown at FIG. 6 wherein the spool 142 is engaged within the reduceddiameter end bore 140 and the compressed O-ring 146 prevents transfer offluid from the chamber 132 to the ambient, the abutments 136 of thespider member legs 135 in engagement with the tubular body shoulderabutment 138 limiting the forward travel of the spider member 134. Themale member tubular body 49 is peripherally tapered, as shown at 151, tofacilitate introduction of the male member tubular body 49 into thetapered end 126 of the bore 48 of the female member tubular body 47.

The male member tubular body 50 has an annular end face 153 which,during engagement of the male member 46 within the female member 44,engages the annular end face 120 of the cup-shaped spool valve 92disposed within the bore 48 of the female member tubular body 47,progressively retracting the cup-shaped valve spool 92 from its positionshown at FIG. 6 to the position shown at FIG. 5. During engagement ofthe male member 46 into the female member 44 the elastomeric O-ring 118in the internal groove 116 in the bore 48 of the female member tubularbody 47 engages the peripheral cylindrical surface 50 of the male membertubular member 49 such that when the annular end face 153 at the tip ofthe male tubular member 49 has retracted the valve spool 92 sufficientlyas to cause the enlarged head 94 on the end of the rod 78 to be nolonger disposed within the bore 106 in the valve spool 92, hydraulicfluid is allowed to circulate to and fro relative to the chamber 90within the female member tubular body 42 and the chamber 132 within thebore 128 of the male member tubular body 49, as a result of the end face100 of the enlarged head 94 of the rod 78 engaging the end face 148 ofthe spool 142 on the end of the spider member 134 causing the spool 142and the spider member 134 to be retracted wtihin the bore 128, and thusdisengaging the spool 142 from within the reduced diameter bore 142against the tension of the spring 150, thus opening a direct fluidcommunication between the chambers 90 and 132. As the male member 46 isprogressively pushed into the female member 44, and the spool valve 92is progressively retracted, the elastomeric O-ring 112 in the internalgroove 114 in the bore 48 of the female member tubular body 47elastically encircles and engages the peripheral surface 50 of the malemember tubular body 49, further ensuring, in co-operation with theelastomeric O-ring 118, that no fluid leaks to the ambient.

In the coupled position illustrated at FIG. 5, a resilient snap ring154, disposed in a peripheral groove 156 formed in the peripheralcylindrical surface 50 of the male member tubular body 49 and which hasbeen progressively contracted while being pushed against the convergingtapered entrance surface 126 of the bore 48 in the female member tubularbody 47, has been allowed to expand when reaching the internal groove122 proximate the open end of the bore 48 in the female member tubularbody 47. The tapered inner wall 124 of the groove 122 aids in locatingthe snap ring 154 relative to the groove 122. The snap ring 154 freelyexpands such as to be fully engaged within the groove 122 with thetrailing face of the snap ring 154, engaged in solid abuttingrelationship with the straight radial wall 125 of the groove 122, suchthat when the connector female member 44 and the connector male member46 are coupled, as shown at FIG. 5, unauthorized separation of the twomembers is prevented.

For coupling the end of the conduit 26 to the master cylinder 28, FIG.1, by means of the leakproof quick-connect connector 32, or for couplingthe end of the conduit 26 to the slave cylinder 18, FIG. 2, by means ofthe quick-connect connector 32 or, alternatively, for connecting bothends of the conduit 26 to a respective cylinder, FIG. 3, by way of aleakproof quick-connect connector 32 on each end of the conduit 26, itis preferable to attach the connector female member 44 to the respectivecylinder or to form the female member integral with the cylinder. Allthat is required is to provide a bore for installation therein of therod 78 and of the spool valve 92, the bore such as bore 48 beingdisposed in direct communication with the internal bore 160 of themaster cylinder 28, as schematically illustrated at FIG. 8, or theinternal bore 48 being part of the passageway leading into the fluidchamber of the slave cylinder.

FIG. 8 illustrates an example of structure for connecting the end of theconduit 26 provided with a connector male member 46 to a master cylinder28, the tubular body 47 of the connector female member 44 being formedintegral with the housing of the master cylinder 28 which, in theexample of structure illustrated, is made of plastic. The bore 160 ofthe master cylinder 28 is placed in direct communication with the femalemember bore 48. The perforated circular plate 74 supporting the rod 78is mounted at the bottom of the bore 48 abutting against an annularshoulder 162 and held in position by a spring steel snap ring 164engaged in an internal groove 166. The remaining of the structureillustrated at FIG. 8 is exactly the same as the structure of theleakproof quick-connect connector 32 previously described with moreparticular detail in reference to the structure illustrated at FIGS.5-7.

Preferably, the male member tubular body 49 and the female body tubularbody 47, FIGS. 5-6, and the end caps 52 are made of metal or metalalloys, such as steel or aluminum alloy for example. Preferably, thespider member 134 is made of a plastic molding and the cup-shaped valvespool 92 is also made of plastic. The rod 78 may be made of metal orplastic. However, it will be readily apparent that the tubular bodymembers 49 and 47 may also be made of plastic, and in structures whereinone of the tubular member body is made integral with the master cylinderhousing or the slave cylinder housing, it is evidently made of the samematerial as the cylinder housings themselves.

Whatever the structure adapted for particular applications, thehydraulic apparatus of the invention is conveniently prefilled withhydraulic fluid and pretested as described in detail in U.S. Pat. Nos.4,503,678 and 4,506,507, the two halves of the leakproof quick-connectconnector 32 being coupled by means of an appropriate clampingmechanism, the interlocking ring 154 being omitted. After prefilling ofthe hydraulic apparatus with hydraulic fluid and testing, the two halvesof the connector 32 are uncoupled, the ring 154 is installed in itsgroove 156 in the peripheral surface 50 of the male member tubular body49, and the diverse components are shipped to a motor vehiclemanufacturer, prefilled with hydraulic fluid, for installation on amotor vehicle.

Alternatively, and as illustrated schematically at FIGS. 9 and 10, thediverse modular components of the hydraulic apparatus may be prefilledindividually with hydraulic fluid. FIGS. 9 and 10 illustrate anapparatus and method for prefilling the hydraulic apparatus of FIG. 3 inits two separate modular components, one consisting of the mastercylinder 28 with a length of flexible conduit 26 readily installed bymeans of a conventional connector 34 onto the master cylinder 28, thefemale member 44 of the leakproof quick-connect connector 32 beinginstalled at the end of the length of flexible conduit 26, and a secondlength of flexible conduit 26 being connected by means of a conventionalconnector 34 to the slave cylinder 18 at other end being provided withthe female member 46 of the quick-connect connector 32.

As illustrated at FIGS. 9 and 10, the hydraulic fluid filling apparatus200 comprises a supply of hydraulic fluid 202, and a source of suctionor vacuum 204 connected through a three-way valve 206 to a line 208having an appropriate fitting generally designated at 210. Although thefitting 210 may take any appropriate form that fits a complementary halfof the connector 32, provided with appropriate means for opening theport of the half connector, it is readily apparent that for the sake ofconvenience the fitting 210 may actually be a male member 46 when it isdesired to fill with hydraulic fluid the portion of the hydraulicapparatus terminated by a connector female member 44, FIG. 9, and afemale member 44 where it is desired to couple the hydraulic fluidfilling apparatus 200 to a portion of the hydraulic apparatus terminatedby a connector male member 46, FIG. 10.

As shown at FIG. 9, the fitting 210, taking the form of a connector malemember 46, is coupled to the connector female member 44, on the end ofthe length of flexible conduit 26, by means of a clamping means 212, theresilient snap ring 154 (FIGS. 5-6) being omitted such that after thefilling operation has been effected, and the clamping means 212released, the fitting 210 is readily disconnected from the connectorfemale member 44. In the clamped position illustrated in the drawing,the line 208 is in fluid communication with the length of flexible line26, which in turn is in communication with the fluid chamber within themaster cylinder 28, the fluid chamber within the master cylinder 28being in fluid communication with the hydraulic fluid reservoir 29 inview of the extended position of the pushrod 30 as held by the clip 42causing the piston, not shown, in the master cylinder 28 to be in aretracted position unmasking the port between the fluid chamber in themaster cylinder and the reservoir 29. The valve 206 is switched to thepositive placing the vacuum source 204 in communication with the conduit208, and the conduit 20 and the master cylinder 28, via the fitting 210and the connector female member 44 such as to evacuate atmospheric airtherefrom. The test of the integrity of the hydraulic apparatus portionmay be effected by maintaining the vacuum and switching the valve 206 toa closed position, and measuring the vacuum in the line 208 over apredetermined period of time by way of a gauge 214. Subsequently, thevalve 206 is turned to a position placing the hydraulic fluid supply202, preferably maintained at a pressure slightly higher thanatmospheric pressure, in communication with the line 208 such as to fillthe length of flexible conduit 26, the master cylinder 28 and the fluidreservoir 29 with hydraulic fluid, together with the chamber 90 withinthe connector female member 44. As the clamping means 212 is releasedand the fitting 210 and connector female member 44 become progressivelyuncoupled, the spool valve 92 is progressively displaced, under theaction of the spring 108 in a direction that increases the volume of thefluid chamber 90, until the port defined by the bore 106 at the tip ofthe spool valve 92 is closed by the enlarged head 94, provided with theO-ring 98, as illustrated at FIG. 6 with respect to the connector femalemember 44.

FIG. 10 illustrates the fitting 210, in the form of a connector femalemember 44, mounted on the end of the line 208 of the filling apparatus200, in clamped coupling engagement with the connector male member 46 onthe end of the length of flexible conduit 26 connected to the slavecylinder 18, preparatory to evacuating the hydraulic apparatus modularportion from atmospheric air, testing and filling with hydraulic fluidas previously explained.

It will be readily apparent to those skilled in the art that the fillingapparatus 200 may be used with appropriate fixturing and clampingmechanisms for filling any modular portion of a hydraulic apparatusprovided with one-half of a full quick-connect connector 32 at themaster cylinder end of the conduit 26, FIG. 1, at the slave cylinder endof the conduit 26, FIG. 2, at some point between the ends of the conduit26, FIG. 3, or at both ends of the conduit 26, FIG. 4.

The structure of FIG. 4 may also be filled with hydraulic fluid in theform of two separate modular units, one consisting of the slave cylinder18, the other consisting of the master cylinder 28, and the thirdconsisting of the conduit 26 on each end of which is mounted a halfconnector such as, for example, a connector male member 46, a connectorfemale member 44, or a female member on one end and a male member on theother end. The filling and testing apparatus 200 is conveniently used inthe same manner as previously described for the purpose of filling eachseparte modular unit, including the conduit 26. The conduit 26 isindividually filled by being first evacuated from atmospheric air,tested as to integrity if so desired, and subsequently filled withhydraulic fluid through one of the half connectors at one end of theconduit. The half connector at the other end of the conduit 26 remainsclosed during evacuation of the atmospheric air as long as the force ofthe spring 108, FIG. 6, urging the spool valve 92 to the positionclosing the connector female member 44 is high enough to overcome theatmospheric pressure applied on the end of the spool valve, instructures where a female member 44 is mounted on the free end or onboth ends of the conduit 26, and as long as the force exerted by thespring 150 urging the spider member 134, in the connector male member46, to a closed position is sufficient to overcome the atmosphericpressure applied to the frontal area of the end face 148 of the spool142 on the end of the spider member, in structures having a connectormale member 46 mounted on the free end of the conduit 26. For example,in a connector 32 according to the present invention having an overalldiameter of about 24 mm. and an internal diameter of about 16 mm. forthe bore 48 of the connector female member 44, all other dimensions ofthe elements being proportionally at the same scale, the coil spring 108in the connector female member 44 needs to exert only a force of 1,800grams, or 65 oz., and the coil spring 150 in the connector male member46 needs to exert a force of only 300 grams, or 11 oz.

The leakproof quick-connect fitting or connector 32 heretofore describedis of the one-way type. In other words, once the two halves of theconnector, namely the female member 44 and the male member 46, arereconnected on a motor vehicle assembly line, for example, the internallocking between the members provided by the snap ring 154 beingpartially disposed in the groove 156 on the periphery of the male membertubular body 49 and in the groove 122 in the surface of the bore 48 ofthe female member tubular body 47, the male member 46 can no longer beuncoupled from within the female member 44. Such an arrangementpreserves the integrity of the system and prevents tampering byunauthorized persons. However, it presents the inconvenience that if oneof the components requires repair or replacement, the whole apparatusmust be replaced, especially in sealed units where no provisions aremade for replenishing the supply of hydraulic fluid and for bleeding theapparatus. It also presents the inconvenience that if work is to beeffected on the motor vehicle engine, clutch or transmission, whichrequires removal of the affected component from the motor vehicle, theslave cylinder cannot be readily disconnected from the master cylinder.Such inconvenience is avoided by the modified connector structure ofFIGS. 11-12, requiring the use of a special tool for disconnecting thetwo halves of the leakproof quick-connect connector 32. An example ofsuch special tool is illustrated at 220 at FIGS. 11-13.

As shown at FIGS. 11-12, the modification that permits uncoupling of thetwo halves of the connector 32 consists in forming a plurality of slots222, for example three, or four as illustrated, extending radiallythrough the wall of the female member tubular body 47 from the peripherythereof to the groove 122. The tool 220 takes the form of a partial ring224 hinged at 226, and provided with a pair of symmetrically disposedextending handles 226. Four tangs 228, in the example of structureillustrated, each corresponding to one of the slots 222, are disposed at90° from each other, radially projecting inwardly relative to the ring224. Each tang 228 is pivotally mounted on one surface of the ring 224by means of a pivot pin 230. The ring 224 has a shallow recess 232, bestshown at FIG. 13, at the location where each tang 228 is pivotallyattached to the ring, such as to permit only limited pivoting of thetang 228 about the pivot pin 230. Other means, such as return springs,may be used for urging the tangs 228 to a radial neutral position whilestill permitting limited pivoting facilitating introduction of the tipof each tang in a slot 222 after opening the tool 220 about the hinge226 by spreading apart the handles 226 such as to permit the ring 224 toencircle the connector 32. Each tang 228 has a tapered tip 234 tofacilitate introduction of the tip into a slot 222 and, when the handles226 are manually pressed towards each other, the tip end surface 236 ofthe tang engages the outer surface of the ring 154 and compresses thering to the bottom of the groove 156, thus causing the peripheralsurface of the ring 154 to be flush with the peripheral surface 50 ofthe male member tubular body 46. The ring 154 being no longer engagedpartially in the groove 122 in the female member tubular body 47, thefemale member 44 and the male member 46 may be uncoupled. If so desired,the slots 222 may be protected by a turn of adhesive plastic tape afterinstallation of the hydraulic control apparatus of the invention on amotor vehicle, to prevent introduction of dirt in the slots 222 that mayinterfere with the operation of the tool 220 when it is desired todisconnect the two halves of the connector 32. It will be immediatelyapparent to those skilled in the art that the requirement for a specialtool, such as the tool 222, will normally be a deterent to any attemptby unauthorized persons to uncouple the two halves of the connector 32so provided with the slots 222.

As illustrated at FIGS. 14-16, the present invention has manyapplications, more particularly in the automotive field. For example, asillustrated at FIG. 14, the present invention permits to design a motorvehicle hydraulic brake system, as illustrated generally andschematically at 300, made of prefilled pretested modular units. For thesake of illustration, the motor vehicle hydraulic brake system 300 isshown as comprising a brake pedal actuated master cylinder 302, a pairof front wheel brake drums or disks 304 each actuated by an appropriateslave cylinder, not shown, and a pair of rear brake drums or disks 306operated by slave cylinders, not shown. In the example of structureillustrated, the master cylinder 302 is connected by a conduit 308 via aT-connector 310 and separate conduits 312 to the slave cylinder of thefront wheel drums or disks 304. A conventional connector 34 connects oneend of the conduit 308 to an outlet of the master cylinder 302, while aconventional connector 34 connects the other end of the conduit 308 tothe inlet of the T-connector 310. A leakproof quick-connect connector 32connects the free end of each wheel conduit 312 to the T-connector 310.The master cylinder 302, together with the line 308 and the T-connector310 form therefore a modular unit which may be individually filled withhydraulic fluid. Each slave cylinder operating the brake drum or disk ofthe front wheel 304 together with the corresponding wheel or conduit 310form separate modular units which may be filled with hydraulic fluidindividually and connected, on the motor vehicle assembly line, to theT-connector 310 by means of the leakproof quick-connect connector 32.

Similarly, the master cylinder 302 is connected through a conduit 314 toa T-connector 316 distributing hydraulic fluid through separate wheelconduits 318 to the slave cylinder operating the brake drums or disks ofthe rear wheel 306. In the example of structure illustrated, the conduit314 is attached to a second outlet of the master cylinder 302 by meansof a leakproof quick-connect connector 32, and the other end of theconduit 314 is connected to the inlet of the T-connector 316 by means ofa conventional connector 34. The modular unit consisting of the line 314and the T-connector 316 can thus be filled separately with hydraulicfluid as a single modular unit. Each wheel conduit 314 being connectedto the T-connector 316 by means of a leakproof quick-connect connector32, the assembly consisting of the rear wheel conduit 318 and the slavecylinder actuating the brake shoe or disk pad of the rear wheel drums ordisks 306 may be filled separately with hydraulic fluid each as amodular unit which, on the assembly line, are connected into thehydraulic brake system 300 by means of the leakproof quick-connectconnectors 32.

It will be appreciated, by those skilled in the art, that a hydraulicbrake system, according to the example of structure of FIG. 14, orsimilar structures provided with prefilled and pretested separatemodular units, allows extreme flexibility in installing a hydraulicbrake system on a motor vehicle, on the assembly line, modular unit bymodular unit, and to connect the whole brake hydraulic system, withoutrequiring the necessity of assembling hydraulic brake systems on a motorvehicle and filling the systems after installation. Also, it permits toeffectuate repairs by replacing modular units of a brake system, withoutthe requirement of purging the whole system and refilling with hydraulicfluid after the repair or replacement of components has been effected.

FIG. 15 illustrates an example of motor vehicle throttle hydrauliccontrol apparatus 400, as disclosed in copending application Ser. No.555,668. Such a system comprises principally a master cylinder 402 whoseinput member or pushrod 404 is operated by an accelerator pedal 406, anda slave cylinder 408 having an output member 410 actuating an enginethrottle lever 412, the master cylinder 402 being connected to the slavecylinder 408 by a flexible conduit 414. In the example of structureillustrated, the conduit 414 is connected at one end to the mastercylinder 402 through a leakproof quick-connect connector 32, and isconnected to the slave cylinder 408 at its other end also by means of aleakproof quick-connect connector 32.

Such a structure permits to fill with hydraulic fluid, and testindividually, the master cylinder 402 as a single modular unit, theconduit 414 as a second modular unit and the slave cylinder 408 as athird modular unit, install the master cylinder 402 and the slavecylinder 408 on a motor vehicle, and connect them with the conduit 414which may be routed as required through the motor vehicle enginecompartment, and which may be routed over long distances as, forexample, in installations in rear engine motor vehicle. It is evidentthat, if so desired, the conduit 414 may be connected to one of thecylinders by a conventional cheaper connector, and that the cylinderwith the conduit 414 thus attached thereto forms a separate modular unitwhich may be individually filled with hydraulic fluid and tested.

FIG. 16 schematically illustrates another example of application of theinvention to a hydraulic shift control for a motor vehicle, such asdisclosed in detail in copending application Ser. No. 555,666. Thehydraulic shifter, designated generally at 500, comprises a doubleacting master cylinder 502 having an input member or pushrod 504reciprocable by a shift lever 506 under the control of the motor vehicledriver. The double acting master cylinder 502 is connected via twoflexible conduits 508 and 510 to the double acting slave cylinder 512having an output member 514 operating the shifter 516 on thetransmission casing 518. The shifter system 500 is prefilled andpretested at the factory prior to shipping to the motor vehiclemanufacturer and, if so desired to provide flexibility in theinstallation of the apparatus on a motor vehicle on the motor vehicleassembly line, is supplied in prefilled pretested modular units which,in the example of structure illustrated, consists of the master cylinder502 provided with the conduits 508 and 510 attached thereto by means ofconventional connectors 34, the other end of the conduits 508 and 510being provided with one-half of a leakproof quick-connect connector 32,the other half of which is made integral with the slave cylinder 512.The slave cylinder 512 may thus be filled separately with hydraulicfluid and tested such as to form a separate modular unit.

Having thus described the present invention by way of examples ofstructure well designed for achieving the objects of the invention,modifications whereof will be apparent to those skilled in the art, whatis claimed as new is as follows:
 1. A method of prefilling a hydraulicapparatus prior to shipment of said hydraulic apparatus to a user, saidhydraulic apparatus comprising a master cylinder, a remote slavecylinder and a conduit connecting said master cylinder to said slavecylinder, said master cylinder, said slave cylinder and said conduitbeing supplied in the form of at least two separate modular units eachcapable of being coupled to the other by a leakproof connector havingtwo interengageable complementary members having each a port providingfluid communication between said members when coupled together and meansclosing said ports when uncoupled, said method comprising separatelyfilling with hydraulic fluid each modular unit of said hydraulicapparatus provided with one of said complementary members, and providingsaid connector complementary members with one-way interlocking meanspreventing disconnect of said members after said members have beencoupled by the user.
 2. The method of claim 1 wherein one of saidconnector complementary members is mounted on one end of said conduit,and the other is mounted on said master cylinder.
 3. The method of claim1 wherein one of said connector complementary members is mounted on oneend of said conduit and the other is mounted on said slave cylinder. 4.The method of claim 1 wherein said leakproof connector is mounted atsome intermediary position between the end of said conduit.
 5. Themethod of claim 1 wherein a first leakproof connector has one of itscomplementary members mounted on an end of said conduit and the other ofits complementary members mounted on said master cylinder, and a secondleakproof connector has one of its complementary members mounted on theother end of said conduit and the other of its complementary membersmounted on said slave cylinder.
 6. The method of claim 1 wherein atleast one of said modular units is filled with hydraulic fluid throughsaid connector complementary member.
 7. The method of claim 2 wherein atleast one of said modular units is filled with hydraulic fluid throughsaid connector complementary member.
 8. The method of claim 3 wherein atleast one of said modular units is filled with hydraulic fluid throughsaid connector complementary member.
 9. The method of claim 4 wherein atleast one of said modular units is filled with hydraulic fluid throughsaid connector complementary member.
 10. The method of claim 5 whereinat least one of said modular units is filled with hydraulic fluidthrough said connector complementary member.
 11. The method of claim 6comprising evacuating atmospheric air from said modular unit byconnecting said modular unit through said connector complementary memberprior to filling with hydraulic fluid by connecting said modular unitthrough said connector complementary member to a source of hydraulicfluid.
 12. The method of claim 7 comprising evacuating atmospheric airfrom said modular unit by connecting said modular unit through saidconnector complementary member prior to filling with hydraulic fluid byconnecting said modular unit through said connector complementary memberto a source of hydraulic fluid.
 13. The method of claim 8 comprisingevacuating atmospheric air from said modular unit by connecting saidmodular unit through said connector complementary member prior tofilling with hydraulic fluid by connecting said modular unit throughsaid connector complementary member to a source of hydraulic fluid. 14.The method of claim 9 comprising evacuating atmospheric air from saidmodular unit by connecting said modular unit through said connectorcomplementary member prior to filling with hydraulic fluid by connectingsaid modular unit through said connector complementary member to asource of hydraulic fluid.
 15. The method of claim 10 comprisingevacuating atmospheric air from said modular unit by connecting saidmodular unit through said connector complementary member prior tofilling with hydraulic fluid by connecting said modular unit throughsaid connector complementary member to a source of hydraulic fluid. 16.The method of claim 1 wherein said hydraulic apparatus is a motorvehicle clutch control mechanism.
 17. The method of claim 1 wherein saidhydraulic apparatus is a motor vehicle hydraulic brake apparatus. 18.The method of claim 1 wherein said hydraulic apparatus is a motorvehicle hydraulic throttle control apparatus.
 19. The method of claim 1wherein said hydraulic apparatus is a motor vehicle hydraulic gearshifter.